By Benjamin Olenchock, MD, PhD

Editor's Note: In an effort to keep you informed on the latest advances across the entire spectrum of cardiovascular care, I've invited my colleague, Benjamin Olenchock, MD, PhD, from Brigham and Women's Hospital to write about the emerging and evolving field of critical care cardiology.

Cardiovascular critical care is changing and we need to keep pace. In my hospital, as in many others in the United States, patients with an uncomplicated ST-elevation myocardial infarction (STEMI) are admitted directly to the step-down unit, and often leave the hospital in 2 or 3 days without ever setting a foot inside the cardiac intensive care unit (CICU). The CICU, meanwhile, is filled with patients with multisystem organ dysfunction who require multiple forms of mechanical life support. The coronary care unit (CCU) was created in the 1960s for the close observation of patients with myocardial infarction (MI).

Today, the CICU is a complex multidisciplinary environment where we care for patients who are older, with more comorbid medical conditions intertwined with their cardiovascular disease. Patient outcomes in the CICU are often determined as much by the fastidious practice of good critical care medicine (CCM) as by our cardiac interventions.

The Changing Landscape

The formation of the dedicated CCU is credited with as much as a 20% reduction in mortality post-MI. The concept of organizing trained staff and special resources around this vulnerable and critically ill patient population was revolutionary at the time, and remains central to our mission. In the time since this inception, all aspects of coronary care have improved, from primary prevention to acute treatment with stents and better medical therapies.

These improvements have reshaped the modern CICU. Observational studies have shown that the diminishing proportion of CICU patients with STEMI has been replaced by elderly patients with cardiac disease complicated by sepsis, acute kidney injury, and hepatic dysfunction. The need for prolonged mechanical ventilation has increased, while the use of percutaneous coronary interventions and pulmonary artery catheters has stayed stable or decreased. Advances in percutaneous mechanical circulatory support (MCS), extracorporal membrane oxygenation, and therapeutic hypothermia have added new management options and challenges. Modern CICUs require a multidisciplinary team to provide comprehensive critical care, working together to ensure patient safety, prevent complications of our interventions, and make decisions regarding advanced life support options, while remaining attentive to compassionate end-of-life care.

How Can We Adapt?

As heralded by Jason N. Katz, MD, in JACC more than 5 years ago,¹ cardiology is facing its own "critical care crisis." To quote Dr. Katz, "It will be our response... that will profoundly shape the future of our field." The response of the cardiology community to this changing landscape has been discussed previously in CardioSource by Scott Lilly, MD, covered by expert reviews, and addressed by a scientific statement from the American Heart Association on the evolution of critical care cardiology.² My personal journey to cardiac intensive care reflects one of many approaches to these challenges.

I recall the moment I found out where I matched for cardiovascular diseases fellowship. My attending at the time, a specialist in heart failure, congratulated me and then told me: "You know, you won't learn much about ventricular assist devices (VADs) during general cardiology training." This, I thought, was surely incorrect, because even as an internal medicine resident I understood that VADs would take on a greater role in the future of cardiology. However, I came to appreciate that, given the extensive requirements of general fellowship, extra training of this type is very challenging to accommodate. Amidst the many competing skills that require "Level I" knowledge, there is simply not enough time to gain the exposure necessary to develop more advanced skills in some areas.

The creation of subspecialty training in advanced heart disease is a good example of how the cardiology community has adapted to new clinical and training needs. Fast-forward a few years, and now I attend in a CICU where 10-20% of our patients have some form of percutaneous or durable MCS, a sizable fraction of patients are ventilated or require renal replacement therapies, and severe pulmonary hypertension is commonplace. Taking primary responsibility for such patients requires a set of skills that have begged for additional experience. My personal approach was to seek additional training in CCM through a partnership with our pulmonary-CCM fellowship. With 1 additional year of training that included 6 months of rotations in CCM (all outside the CICU), I acquired a set of skills and perspective that has equipped me well for the challenges that I now face frequently in the CICU. In this coming year, I will sit for the certification exam in CCM, having taken one of several possible pathways to dual certification in cardiology and CCM.

What's Next?

There is a need for us to tackle these challenges together as a cardiology community. Through the course of my training, I was introduced to many fellows and residents with similar interests, as well as training directors and CICU leaders who are interested in cultivating opportunities for advanced training in critical care cardiology at their own institutions. The interest in this pathway by trainees is striking, as are the range of opinions regarding its value. A recent study surveyed ICU directors regarding staffing of ICUs, the role of trained intensivists in CICUs, and opinions regarding the need for cardiologists with focused clinical experience in CCM.³ While there is clearly a diversity of opinion on these issues, the majority of participants identified an unmet need for cardiologists who have specialized skills in CCM. The mixed opinion in other areas of the survey reflects the need for more rigorous study of alternate organizational models in the CICU.

There is certainly no "one-size-fits-all" approach to CICU staffing and structure. Aimed at supporting interchange of ideas, a group of academic cardiac intensivists have created an online community (criticalcarecardiology.com and @CritCareCardiol) to foster discussion, gather research, and share information relevant to the cardiac intensivist.

The CCU of old has evolved and there is no going back. It is incumbent upon us to consider organization and training strategies that embrace innovation and prepare our discipline for the future of critical care cardiology.

References

1. Katz JN, Turer AT, Becker RC. J Am Coll Cardiol. 2007;49;1279-82.
2. Morrow DA, Fang JC, Fintel DJ, et al. Circulation. 2012;126(11):1408-28.
3. O’Malley RG, Olenchock B, Bohula-May E, et al. Eur Heart J Acute Cardiovasc Care. 2013;2:3-8.

Benjamin A. Olenchock, MD, PhD, is an instructor in medicine at Harvard Medical School, and a cardiologist in the division of cardiovascular medicine at Brigham and Women's Hospital.